From a01c54a900767863f894d3013343997b7ddca6ce Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 28 Oct 2020 15:08:09 +0100 Subject: [PATCH] Revert "Revert "fs: Allow a NULL pos pointer to __kernel_read"" This reverts commit aeffda3c613cd8b29dc8454e154eb94f0c21cb36. Bug: 171770067 Signed-off-by: Greg Kroah-Hartman Change-Id: I433aead8411131865de1cff8957d4708009142ba --- fs/read_write.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 5d731929259d..4bf7ca7e7094 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -449,11 +449,12 @@ ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos) return warn_unsupported(file, "read"); init_sync_kiocb(&kiocb, file); - kiocb.ki_pos = *pos; + kiocb.ki_pos = pos ? *pos : 0; iov_iter_kvec(&iter, READ, &iov, 1, iov.iov_len); ret = file->f_op->read_iter(&kiocb, &iter); if (ret > 0) { - *pos = kiocb.ki_pos; + if (pos) + *pos = kiocb.ki_pos; fsnotify_access(file); add_rchar(current, ret); }